A known electrophotographic image forming apparatus includes a fixing unit that is configured to fix a developer image onto a recording sheet, such as a plain, glossy, and transparent sheet, by heat.
In a small-sized image forming apparatus in connection with an information processing device, such as a personal computer, a recording sheet ejected from the fixing unit is turned upward about 180 degrees and ejected onto a sheet ejection tray disposed above the fixing unit.
A path for conveying a recording sheet (hereinafter referred to as a conveyance path) has generally a U-shape from the fixing unit to the sheet ejection tray. The conveyance path is defined by an inner guide forming an inner guide surface of the U-shaped conveyance path and an outer guide disposed facing the inner guide and forming an outer guide surface of the conveyance path.
In the above image forming apparatus, the inner guide and a part of the ejection tray are integrally formed into a tray member, which is configured to be attached to and removed from the ejection tray. With this configuration, the image forming apparatus can be reduced in height while improving the removability of the fixing device.
For a low-profile image forming apparatus, if the lower end of the sheet ejection tray is lowered further than the upper end of the fixing device, the fixing device may interfere with the lower end of the sheet ejection tray when horizontally attached to or removed from the rear of the image forming apparatus.
As described above, the U-shaped conveyance path continuing from the fixing unit to the sheet ejection tray may be defined by the inner guide forming the inner guide surface of the conveyance path and the outer guide disposed facing the inner guide and forming an outer guide surface of the conveyance path. When viewed from the rear side of the image forming apparatus, that is, in a direction where the fixing device is attached to and removed from the image forming apparatus, the outer guide overlaps a part of the inner guide.
Thus, when the inner guide is moved horizontally, the outer guide may interfere with this movement. When the inner guide is attached to or removed from the image forming apparatus, the inner guide and the outer guide may be highly damaged on their respective guide surfaces.
When the inner guide is attached to or removed from the image forming apparatus, the inner guide needs to be moved obliquely and horizontally so as to prevent the inner guide from interfering with the outer guide. This may complicate attaching or removing the inner guide and the fixing unit to or from the image forming apparatus.
The guide surfaces of the inner guide and the outer guide are configured to guide a recording sheet in sliding contact therewith. If the guide surfaces are damaged, it is difficult to convey the recording sheet smoothly, which may lead to problems such as jamming.